An "Asset" Rating is:

• a calculated rating based on standard weather and building use
• similar in principle to "typical use" consumption figures for cars
• useful when comparing two buildings with different users, i.e. provides like-for-like figures

An "Operational" Rating is:

• based on measured energy use
• takes how the building is used and managed
• useful for energy managers and potential users of the building because it includes factors they control.

NB. the relevant CEN standards have adopted the terms "Calculated Rating" and "Measured Rating".  These are equivalent to "Asset Ratings" and "Operational Ratings" respectively.

Author:  Roger HITCHIN (BRE)
Date:   07/04/06